Measuring device



Patented nec. 15, i925.

STES

.FAEEN'F HAROLD l'. RUDD, OF EBGEVJOGD. AND ALLAN P. BEHEER, 0FVVILKITSBURG, PENN- SYLVANIA, ASSIGNES TG WESINGHOSE ELECTRC 8cMANUFACTRIJG COM- ??ANY, A CORPORLTIGN OF EDENTSYLVANIA.

MEASURING DEVICE.

Application filed August 255, 1918.

Be it known that we H iuonn H. ltr'nn, a citizen oil" the l'nitedStates. and a resident ot Edgewood, in the county ot Allegheny and Stateof Pennsylvania, and ALLAN Bimota?, a citizen oi the United States, anda resident ot lllillrinsburi. in the county of Allegheny and State otPennsylvania, have invented a. new and usctul Improvement in Measuiingi`levices, ot which the following' is a speciiication.

(hir invention relates to measuring devices and particularly to meanstor indicating the temperature of translating' devices.

@ne object ot our invention is to provide a device tor indicating' themean temperature ot the windings oi a translating device.

Another object ot' our invention is to provide a temperature-indieatingdevice, ot the above indicated character, that shall be inductivelyrelated to the translating device.

fr further object ot our invention is to provide an. indicating deviceof the above indicated character that shall be simple and inexpensive toconstruct and effective in its operation.

ln practicing' our invention, we provide a windinggf that is inductivelyassociated with. and subjected to the temperature of, the transformer orother translating device, the temperature ot which is to bedetermined. Asecond winding' having a relatively low or Zero temperature coeiiicientis similarly associated with the transformer. Means, such as an. electroresponsive device, is provided for indicating' temperature in accordancewith the difference in the current tiaversin n` the two windings. Sincethe numbers of turns and the normal resistances of the windings areequal, the difference in current traversing the same is proportional tothe change in resistance of one of the windings, and, since theresistance of the winding varies with the temperature to which it issubjected, the diii'erence in current traversing the windings is anindication of the temperature of the transformer.

Fig'. l of the accompanying drawings is a diagrammatic view of atemperature-measuring device embodying our invention, and Fig. 2 is adiagrammatic view of a modified Serial No. 251,392.

'Form of temperature-measuring device embodyinnour invention.

A transformer l, comprising' a magnetircable core member 2, a primarywinding 3 and a secondary winding 4, is pr vided with atemperature-measurina device that adapted to indicate the actualtemperature to which the windings 3 and fl; o'l" the transformer aresubjected.

A winding' 6, having,` a relatively high temperature coefficient, isdisposed around the core member 2 between the two portions ot thesecondary winding 4. The winding 6 is inductively associated with. thewindings 3 and 4; and is connected in series with a resistor 7. Atwo-part winding 8 is disposed in inductive relation to the windings otthe transformer l, the two parts ot which are distributed with respectto the winding G. The winding` 8 is of the same number of turns as thewinding' 6 and is formed ot material having' a relatively low or evenzero temperature coetiicient. The winding' 8 is connected in series witha resistor 9. The windings 6 and 8 are so wound, with respect to thetransformer l, that the voltages induced therein are in opposition toone another.

The primary winding' l0 ot a transformer ll Vis operatively connectedacross the re sistor 7, and the secondary winding' l2 is connected to avoltagedneasuring instru ment 13. Similarly, the primary ,winding lll ofthe transformer l5 is connected across the resistor 9, and the secondarywinding 1G is connected in series with the secondary l2 of thetransformer ll. By this arrangement, the measuring instrument 13 isadapted to indicate the difference in potential drop across theresistors 7 and 9.

Since the windings 6 and 8 are of the same number of turns and, sincethey are adapted to oppose one another, the difference in currenttraversing the same will be caused only by a change in resistance in thewindings. However, since the resistance of the winding 6 varies inaccordance with the temperature to which it is subjected the differencein currents traversing the resistors 7 and 9 and, consequently theindication of the instrument 13 will be an indication of the temperatureof the transformer 1.

2 Lacasse In F ig. 2 of the drawings, like reference numerals refer tosimilar parts of the device shown in Fig. 1. ln this device, the poten,Atial drop across the resistors 7 and 9 is adapted to be indicated by adifferential measuring instrument 1'?. That is, the secondary winding 12of the transformer 11 is connected to the actuating winding 18 of oneelement 19 of the meter 17 and the secondary winding 16 of thetransformer 15 is connected to the actuating winding 20 of anotherelement 21 of the meter. The windings 18 and 2O are adapted to actuatetheir respective armatures 22 and 28 in opposite directions, therebycausing a pointer 24, that mounted on a shaft upon which the armatures22 and 23 are also mounted to indicate the difference in the currentstraversing the windings 6 and 8. The armatures are provided with theusual forms of controlling devices not shown) to preclude rotationthereof.

It will be understood that the same result may be obtained by disposingthe windings 6 and 8 in the same direction on the core member 2 andconnecting the same to oppose each other. However, in order that thereactance effect of the two windings be identical, it is essential thatan even and equal number of turns of the windings 6 and 8 be transposedat the middle of the same, This will equalize t-he effect of transformerreactance or leakage, in so far as the windings 6 and 8 are concerned.

Our invention is not limited to the specific devices illustrated, as itmay be variously modified without departing from the spirit and scope ofthe invention as set forth in the claims.

Ve claim as our invention:

1. A temperature-measuring device for a transformer comprising anexploring wind ing having a relatively high temperature coefficient, anexploring winding having a relatively low temperature coefficient, saidwindings being inductively and thermally associated with thetransformer, means for causing the currents traversing the windings toexert opposing effects, and means for indicating the resultant of saideli cts.

2. A tempcinture-measuring device for a transformer comprising a windinginductively related to the transforn'ier, a second winding` having zerotemperature coefficient also inductively related to the transformer, andmeans for indicating the di florence in the currents traversing thewindings.

8. A teinperatiire-measuring device for a transformer comprisingtwowindings having di'ii'erent temperature coeiiicients indue tively7associated with, and subjected to, the temperature et the transformer,and electrical means connected to the windings for indicating thediiference in current travers ing the same.

1i. A temperature-measuring device for a translatingI device comprisingtwo windings having different temperature coefficients, said windingsbeing` inductively associated with, and subjected to, the temperature ofthe translating device, and means connected to the windings forindicating the difference in current traversing the same.

5. A tempcinture-measuring device for a translating device comprising awinding., second winding having a relatively low temperaturecoetiicient, said windings being` inductively and thermally associatedwith the device, and means connected to the windings for indicating thedifference in current traversing the windings.

6. A temperature-measuring device for a translating device comprising awinding, a second winding having a relatively low temperaturecoefficient, said windings being inductively associated with, andsubjected to the temperature of, the translating device, and anelectro-responsive device for indicating the difference in currenttraversing the windings.

In testimony whereof, we have hereunto subscribed our names.

HAROLD H. RUDD. ALLAN l?. BENDER

